This is one gem, that I got from a friend of mine. The puzzle in its simplest form goes like this:

There are a set of 8 balls. Out of which 7 are of same mass, and the remaining one is heavier than the rest. What is the minimum number of weighings required to find out the heavier ball? i.e. How many times do you require to use the balance?

Try to solve this puzzle at ur best........i will tell u the answer on monday.Let me see hw many of u r the real challenger's.........

Most see airport security as a pain. Some feel violated. When you watch this clip, you'll understand why they want your cell phone through

the x-ray machine. If you get asked to test your cell phone at the airport, this is the reason. Cell phone guns have arrived.

They are real. The attached video clip shows how cell

phone guns operate. These phones are not in the U.S.

yet, but they are in use overseas.

Beneath the digital phone face is a .22 caliber handgun capable of firing four rounds in rapid succession using the standard telephone keypad. European law enforcement officials are stunned by the discovery of these deadly decoys. They say phone guns are changing the rules of engagement in Europe. Only when you have one in your hand do you realize that they are heavier than a regular cell phone.

Be patient if security asks to look at your cell phone or

turn it on to show that it works. They have a good reason! Wake up to our NEW WORLD!! We shouldn't complain

A group of scientists at Rensselaer Polytechnic Institute claims they've created just such a battery, one that uses the electrolytes naturally found in bodily fluids. The results of the research, detailed in the Aug. 13, 2007, issue of the Proceedings of the National Academy of Sciences, are generating some excitement as part of a new crop of "bio-batteries" that run off of bodily fluids or other organic compounds. (The RPI team claims that theirs could even run on tears or urine.)

RPI batteries:-

RPI's battery is paper-thin, can be cut into a variety of shapes and runs on blood or sweat.

The battery is not only as thin as paper; it essentially is paper. At least 90 percent of the battery is made from cellulose, which makes up traditional paper and other paper products [source: RPI]. Aligned carbon nanotubes make up the other 10 percent, give the paper its conductive abilities and also make it black. The nanotubes are imprinted in the very fabric of the paper, creating what's called a nanocomposite paper. One of the paper's authors said that the battery "looks, feels and weighs the same as paper" [source: RPI].

Using nanotechnology, the battery's small size, flexibility and replenishing electrolyte source -- that is, as long as you eat -- make it ideal for medical applications. When using the battery away from the human body, scientists soaked the paper in an ionic fluid (a salt in liquid form), which provides the electrolytes.

The battery's paper-like construction grants it significant flexibility. The RPI research team believes that the battery could, in the future, be printed in long sheets, which could then be cut into small, custom-shaped batteries. The nanocomposite paper can have holes poked in it or be cut into unusual shapes and continue to function. Several sheets could be lumped together to power medical implants, such as pacemakers, artificial hearts or advanced prosthetics. The battery would easily fit under the skin without causing any discomfort.

Because the ionic liquid used doesn't freeze or evaporate like water, the battery could be employed at a wide range of temperatures: from -100 degrees Fahrenheit up to 300 degrees Fahrenheit. Its temperature resistance and light weight mean that manufacturers of automobiles and airplanes -- both of which require light, durable materials -- may come calling.

The researchers behind the battery claim that their device is unique because it can act "as both a high-energy battery and a high-power supercapacitor" [source: RPI]. Supercapacitors allow for large, quick bursts of energy, potentially extending the technology's already wide range of applications.

The battery, which is considered environmentally friendly because of its lack of chemicals and high cellulose content, was announced in the summer of 2007, but it may be years before it's ready to stream off production lines in long sheets. The RPI research team says that, in the meantime, they're trying to boost the battery's efficiency and to figure out the best method for production.

It's not just researchers at the Rensselaer Polytechnique Institute who are working on bio-batteries. Many other corporations, universities and research foundations are competing to produce viable batteries that can be powered off of organic compounds, especially human fluids. Researchers consider sugar and human blood glucose potentially valuable sources of power because they occur naturally, are easily accessible and don't produce harmful emissions.